Method and machine for making



Feb. 18, HILL. R- 22,842

' l mamon um Incarne rox lujxnle courosrrs- Bonn;

Original Filec Dec. 26, 1942 f '-wfj IN KENTOR /f'wn yBY A TTORNE YSperminute, whereas the corrugator is Reasued Feb. 18, 1947 UNITED STATESPATENT oFFlcE METHOD AND MACHIN FOR MAKING COMPOSITE BOARDS Irving Hill,Lawrence, Kans., assigner, by mesne assignments, to George W.- Swift,Jr., Inc., Bordentown, N. J., a corporation of INew Jersey Original No.2,384,676, dated September 11, 1945,

Serial No. 470,292, December 26, 1942. Application for reissue August 5,1946, Serial No.

assess This invention relates "to a composite board land method ofmanufacturing the saine, and particularly a moisture resistantcorrugated board. The moisture resistant nature and the use of suchboard for the manufacture of moisture resistant containers `require useof a relatively slow adhesive, for example starch formaldehyde urea, insecuring the lining sheets to the corrugated sheet.

While a high quality board is produced with the use of such slow settingadhesive, the slowly setting properties of the adhesive limit the speedat which the corrugated board may be manufactured, that is, thecorrugator and liner applying rolls can not be operated any` faster thanthe timerequired for the adhesive to take the set necessary in retainingthe sheets in assembly. vTo illustrate, when starch formaldehyde ureaadhesive is used, the maximum speed at which the corrugator can beoperated is from 150 to 160 feet adapted to operate at much higherspeeds.

It is, therefore, a principal object of the present invention to providea method by which higher operating speeds may be attained and whichproduces a high quality of moisture resistant board at a reduced cost. l

Afurther object of the inventionis to provide y a vmethod of bonding thesheets to 'form a composite unit by employing a fast setting adhesive inconjunction with the slow setting adhesive so that the fast settingadhesive holds the sheets in assembly during .set of the slowsettingadheslve.

In accomplishing these and other objects of the invention, ashereinafter pointed out, I have pro- `vided an improved method ofmanufacturing moisture resistant corrugated board as illustrated intheaccompanying drawing, wherein: Fig. 1 is a diagrammatic sectionshowing progressof sheets or webs through a machine for manufacturingcorrugated board and illustrating the adhesive applicators arranged inaccordance with the present invention. l

Fig. 2 d.is a fragmentary section through the main corrugating rollillustrating the slow setting adhesive after it has been applied to thetips of the corrugations of the corrugated sheet and showing applicationof the fast setting adhesiveV 6 Claims. (Cl. 154-311) 2 fast and slowsetting adhesives which bond the sheets together to form a compositeunit.

Referring more in detail to the drawing:

In the manufacture of corrugated board the web .from lwhich thecorrugated sheet is formed may be carried in a roll I that is drawntherefrom over a reversing roller 2, a heating roll 3 for conditioningthe web preparatory to corrugation, between guide rollers 4 and 5 andunder tensioning rollers 6 and 1 to the corrugating rolls 3 and 9. Thecorrugated rolls 8 and 9 have intermeshing ribs or teeth III and II toform corrugations I2 in the web as in conventional practice, the rollerIl) being heated. to facilitate formation of the corrugations.

Located in association with the corrugated roll 9 is an adhesiveapplicator mechanism I3 by which a moisture resistant adhesiveis appliedto the tips of the corrugations for bonding a lining sheet 'Il to oneside thereof. The lining sheet is also in the form of a web wound in-aroll I! and extends under a guide roller IB Athat Dresses the liningsheet into bonding contact with the adhesive on the tips of thecorrugations. The corrugated shet and lining sheet are passed over aseries of guide rollers I1, to a reversing roller I8 guided by rollers-23, 24 and 25 into sealing contact with the adhesive applied by theapplicator'v mechanism 20. The mechanism just described is substantiallyconventional equipment used in the manufacture of corrugated board.Howeven. when moisture resistant board is being manufactured theapparatus must be operated at -relatively slow speeds owing to the factthat the adhesive used in bonding this type of board is slow in taking aset sufilcient to prevent disarrangementof the sheets.

This characteristic of the adhesive material restricts manufacturingcapacity of thel machine and I have therefore provided an improvedmethod of bonding the sheets .which method utilizes a fast settingadhesive such as the starch glue in conjunction with the slow settingadhesive such as starch formaldehydeV urea, whereby i a an man1 bona isquickly effected by the rast setfting adhesive so that the machine 'maybe operated at greatly increased speed, thereby increasing thel outputof the machine and reducing the cost or the board under production.

The above may be eil'ected by applying one type I ot adhesive in spaceddots extending transversely and the other adhesive in the form of narrowl rollers'29, which rollers rotate in surface contact with the pickuprollers and in contact with the tips of corrugations asthey are advancedincidental to rotation of the corrugator rolls. While various forms ofapplicator rollers may be used in applying the adhesive, for example acylindrical roller, having Scrapers 3D bearing thereon for removingportions of the adhesive from the applicator rollers so that the rollersapply the adhesive to the tips of the corrugations in the form of aseries of sealing areas 3| spaced apart as indicated at 32. which spaceis adapted to be sealingly contacted with a fast setting adhesiveapplied to the adjacent face of the liner sheet I4 by applicatormechanisms '33 and 34, each including a pan 35 for containing suppliesof fast setting adhesive. Rotatable in the pans are .pickup rollers 38for transferring the quick setting in the form of a series oi' spacedsealing areas and fast setting adhesive applied in stripe form to thelining sheets, it is obvious that the adhesives l may b'e reversed.

What I claim and desire to secure .by Letters Patent is:

l. The method of bonding a lining sheet to a corrugated sheet in forminga corrugated board including, applying a slow setting adhesive tolaterally spaced portions of the tips of said corrugations across thewidth of the corrugated sheet, applying similarly spaced stripes of fastsetting adhesivey along the length of the lining sheet, and bringing thesheets into contact with adhesive on one sheet contacting the spacesbetween the adhesive on the other sheet.

2. The method of bonding sheets in forming a corrugated board including.`corrugating one of said sheets, applying spaced spots of adhesive ontips of said corrugationon the respective sides of the corrugated sheet,applying spaced stripes of a different adhesive to lining sheets,registering the stripes 'with said spaces on said tips of thecorrugations, and bringing said sheets into sealing contact.

3. An apparatus for forming a moisture resistant corrugated boardincluding, means for guiding a plurality of sheets into juxtaposedrelation, means for corrugating anA intermediate sheet, adhesiveapplicator rolls contacting tips of the corrugated sheet, means forscraping adhesive from the applicator rolls whereby the adhesive isapplied by said rolls to the corrugations in spaced adhesive onto aplurality of laterally spaced applicator wheels 31 so spaced that theadhesive areas applied to the face sides ot the liner sheets are in theform of longitudinal stripes I8 which register when the spaces 32between the slow setting adhesive areas on the tips of the lcorrugations of the corrugated sheet. The width of the stripes 38 ofquick setting adhesive is only suiiicient to form the desired initialbond of the sheets so that the sheets are retained in bondedcontactuntil the 4slow setting adhesive is eiecof the stripes to thewidth of the wheels and avoidl overlap of the tWo types of adhesive.

It is abvious that either the wheel type applicators or the roller andscraper type maybe used as either one is effective in applying theadhesives in accordance with the present invention.

It is also obvious that adhesives may be applied in the form of spotsinstead of stripes as described without departing from the spirit of theinvention. 'l

From the foregoing it is obvious that stripes or spots of quick settingadhesive form adequate seals or bonds to retain the sheets in assemblyduring set of the slow setting adhesives. Therefore the corrugated boardmay be produced at a greater speed, for example ,in the instance ofadhesives above noted the corrugating rolls may be increased to speedsof 250 to 26o feet per minute, allowing ample time for setting of thequick setting adhesive.

While I have shown and described the slow setting adhesive applied tothe corrugated sheetv aligning spot-like areas,l means for applyingstripes of adhesive in spaced relation longitudinally of the other ofsaid sheets, and means for bringing the sheets into sealing registry.

4. An apparatus for forming a moisture resist- `ant corrugated boardincluding, means for feeding a plurality of sheets through a fixed path,corrugating means located in the path of one of said sheets forcorrugating said sheet, adhesive applicator means arranged -on oppositesides of the corrugated sheet to contact the corrugations ofthecorrugated sheet for applying a slow settingadhesive to selected areason the tips of said corrugations, and adhesive applicator means spacedfrom the rst-mentioned applicator means and arranged to contact faces ofthe other sheets for applying a fast setting adhesive to. differentialareas onthe faces of said other sheets, said feeding meansbeing arrangedto bring said other sheets into sealing contact with said corrugatedsheet. l

\ 5. The method of bonding longitudinally traveling paper sheets, whichincludes successively producing transverse corrugations in one of saidsheets, successively producing adhesive bearing areas on the tips ofsuch corrugations, which areas on each corrugatio'n are spacedtransversely of the-sheet with respect to each other, and such areas ofsuccessive corrugations being alined longitudinally of the sheet toprovide spaces on said tips between such areas which spaces are alinedlongitudinally of the sheet, progressively producing longitudinallydirected stripes of adhesive upon another sheet in reg ister withrespect to the aforesaid spaces, and progressively pressing thelongitudinally traveling sheets into contact with each other and withthe adhesive stripes on the second mentioned `sheet contacting thelongitudinally alined spaces between the adhesive bearing areas on therst mentioned corrugated sheet.

provide spaces between such areas which spaces 10 are alinedlongitudinally of the sheet, means for producing upon a lining sheet,longitudinally directed stripes of adhesive in register with theaforesaid spaces, and means for progressively pressing said lining sheetinto contact with said tips of the corrugated sheet and with saidadhesive stripes contacting said longitudinally alined spaces on saidtips.

. IRVING HILL.

